X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/b19caaefc277335ed623e0a3b6c80be31fce439c..refs/heads/master:/armsrc/iclass.c?ds=sidebyside

diff --git a/armsrc/iclass.c b/armsrc/iclass.c
index 81ecd01b..3f89ae85 100644
--- a/armsrc/iclass.c
+++ b/armsrc/iclass.c
@@ -3,6 +3,7 @@
 // Hagen Fritsch - June 2010
 // Gerhard de Koning Gans - May 2011
 // Gerhard de Koning Gans - June 2012 - Added iClass card and reader emulation
+// piwi - 2019
 //
 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
 // at your option, any later version. See the LICENSE.txt file for the text of
@@ -10,1070 +11,157 @@
 //-----------------------------------------------------------------------------
 // Routines to support iClass.
 //-----------------------------------------------------------------------------
-// Based on ISO14443a implementation. Still in experimental phase.
 // Contribution made during a security research at Radboud University Nijmegen
-// 
-// Please feel free to contribute and extend iClass support!!
-//-----------------------------------------------------------------------------
-//
-// FIX:
-// ====
-// We still have sometimes a demodulation error when snooping iClass communication.
-// The resulting trace of a read-block-03 command may look something like this:
-//
-//  +  22279:    :     0c  03  e8  01    
-//
-//    ...with an incorrect answer...
-//
-//  +     85:   0: TAG ff! ff! ff! ff! ff! ff! ff! ff! bb  33  bb  00  01! 0e! 04! bb     !crc
-//
-// We still left the error signalling bytes in the traces like 0xbb
-//
-// A correct trace should look like this:
-//
-// +  21112:    :     0c  03  e8  01    
-// +     85:   0: TAG ff  ff  ff  ff  ff  ff  ff  ff  ea  f5    
 //
+// Please feel free to contribute and extend iClass support!!
 //-----------------------------------------------------------------------------
 
+#include "iclass.h"
+
 #include "proxmark3.h"
 #include "apps.h"
 #include "util.h"
 #include "string.h"
+#include "printf.h"
 #include "common.h"
-#include "cmd.h"
+#include "usb_cdc.h"
+#include "iso14443a.h"
+#include "iso15693.h"
 // Needed for CRC in emulation mode;
 // same construction as in ISO 14443;
 // different initial value (CRC_ICLASS)
 #include "iso14443crc.h"
 #include "iso15693tools.h"
-#include "cipher.h"
 #include "protocols.h"
-static int timeout = 4096;
-
-
-static int SendIClassAnswer(uint8_t *resp, int respLen, int delay);
-
-//-----------------------------------------------------------------------------
-// The software UART that receives commands from the reader, and its state
-// variables.
-//-----------------------------------------------------------------------------
-static struct {
-    enum {
-        STATE_UNSYNCD,
-        STATE_START_OF_COMMUNICATION,
-	STATE_RECEIVING
-    }       state;
-    uint16_t    shiftReg;
-    int     bitCnt;
-    int     byteCnt;
-    int     byteCntMax;
-    int     posCnt;
-    int     nOutOfCnt;
-    int     OutOfCnt;
-    int     syncBit;
-    int     samples;
-    int     highCnt;
-    int     swapper;
-    int     counter;
-    int     bitBuffer;
-    int     dropPosition;
-    uint8_t *output;
-} Uart;
-
-static RAMFUNC int OutOfNDecoding(int bit)
-{
-	//int error = 0;
-	int bitright;
-
-	if(!Uart.bitBuffer) {
-		Uart.bitBuffer = bit ^ 0xFF0;
-		return FALSE;
-	}
-	else {
-		Uart.bitBuffer <<= 4;
-		Uart.bitBuffer ^= bit;
-	}
-	
-	/*if(Uart.swapper) {
-		Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
-		Uart.byteCnt++;
-		Uart.swapper = 0;
-		if(Uart.byteCnt > 15) { return TRUE; }
-	}
-	else {
-		Uart.swapper = 1;
-	}*/
-
-	if(Uart.state != STATE_UNSYNCD) {
-		Uart.posCnt++;
-
-		if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {
-			bit = 0x00;
-		}
-		else {
-			bit = 0x01;
-		}
-		if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {
-			bitright = 0x00;
-		}
-		else {
-			bitright = 0x01;
-		}
-		if(bit != bitright) { bit = bitright; }
-
-		
-		// So, now we only have to deal with *bit*, lets see...
-		if(Uart.posCnt == 1) {
-			// measurement first half bitperiod
-			if(!bit) {
-				// Drop in first half means that we are either seeing
-				// an SOF or an EOF.
-
-				if(Uart.nOutOfCnt == 1) {
-					// End of Communication
-					Uart.state = STATE_UNSYNCD;
-					Uart.highCnt = 0;
-					if(Uart.byteCnt == 0) {
-						// Its not straightforward to show single EOFs
-						// So just leave it and do not return TRUE
-						Uart.output[0] = 0xf0;
-						Uart.byteCnt++;
-					}
-					else {
-						return TRUE;
-					}
-				}
-				else if(Uart.state != STATE_START_OF_COMMUNICATION) {
-					// When not part of SOF or EOF, it is an error
-					Uart.state = STATE_UNSYNCD;
-					Uart.highCnt = 0;
-					//error = 4;
-				}
-			}
-		}
-		else {
-			// measurement second half bitperiod
-			// Count the bitslot we are in... (ISO 15693)
-			Uart.nOutOfCnt++;
-			
-			if(!bit) {
-				if(Uart.dropPosition) {
-					if(Uart.state == STATE_START_OF_COMMUNICATION) {
-						//error = 1;
-					}
-					else {
-						//error = 7;
-					}
-					// It is an error if we already have seen a drop in current frame
-					Uart.state = STATE_UNSYNCD;
-					Uart.highCnt = 0;
-				}
-				else {
-					Uart.dropPosition = Uart.nOutOfCnt;
-				}
-			}
+#include "optimized_cipher.h"
+#include "fpgaloader.h"
 
-			Uart.posCnt = 0;
+// iCLASS has a slightly different timing compared to ISO15693. According to the picopass data sheet the tag response is expected 330us after
+// the reader command. This is measured from end of reader EOF to first modulation of the tag's SOF which starts with a 56,64us unmodulated period.
+// 330us = 140 ssp_clk cycles @ 423,75kHz when simulating.
+// 56,64us = 24 ssp_clk_cycles
+#define DELAY_ICLASS_VCD_TO_VICC_SIM     (140 - 24)
+// times in ssp_clk_cycles @ 3,3625MHz when acting as reader
+#define DELAY_ICLASS_VICC_TO_VCD_READER  DELAY_ISO15693_VICC_TO_VCD_READER
+// times in samples @ 212kHz when acting as reader
+#define ICLASS_READER_TIMEOUT_ACTALL     330 // 1558us, nominal 330us + 7slots*160us = 1450us
+#define ICLASS_READER_TIMEOUT_UPDATE    3390 // 16000us, nominal 4-15ms
+#define ICLASS_READER_TIMEOUT_OTHERS      80 // 380us, nominal 330us
 
-			
-			if(Uart.nOutOfCnt == Uart.OutOfCnt && Uart.OutOfCnt == 4) {
-				Uart.nOutOfCnt = 0;
-				
-				if(Uart.state == STATE_START_OF_COMMUNICATION) {
-					if(Uart.dropPosition == 4) {
-						Uart.state = STATE_RECEIVING;
-						Uart.OutOfCnt = 256;
-					}
-					else if(Uart.dropPosition == 3) {
-						Uart.state = STATE_RECEIVING;
-						Uart.OutOfCnt = 4;
-						//Uart.output[Uart.byteCnt] = 0xdd;
-						//Uart.byteCnt++;
-					}
-					else {
-						Uart.state = STATE_UNSYNCD;
-						Uart.highCnt = 0;
-					}
-					Uart.dropPosition = 0;
-				}
-				else {
-					// RECEIVING DATA
-					// 1 out of 4
-					if(!Uart.dropPosition) {
-						Uart.state = STATE_UNSYNCD;
-						Uart.highCnt = 0;
-						//error = 9;
-					}
-					else {
-						Uart.shiftReg >>= 2;
-						
-						// Swap bit order
-						Uart.dropPosition--;
-						//if(Uart.dropPosition == 1) { Uart.dropPosition = 2; }
-						//else if(Uart.dropPosition == 2) { Uart.dropPosition = 1; }
-						
-						Uart.shiftReg ^= ((Uart.dropPosition & 0x03) << 6);
-						Uart.bitCnt += 2;
-						Uart.dropPosition = 0;
-
-						if(Uart.bitCnt == 8) {
-							Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
-							Uart.byteCnt++;
-							Uart.bitCnt = 0;
-							Uart.shiftReg = 0;
-						}
-					}
-				}
-			}
-			else if(Uart.nOutOfCnt == Uart.OutOfCnt) {
-				// RECEIVING DATA
-				// 1 out of 256
-				if(!Uart.dropPosition) {
-					Uart.state = STATE_UNSYNCD;
-					Uart.highCnt = 0;
-					//error = 3;
-				}
-				else {
-					Uart.dropPosition--;
-					Uart.output[Uart.byteCnt] = (Uart.dropPosition & 0xff);
-					Uart.byteCnt++;
-					Uart.bitCnt = 0;
-					Uart.shiftReg = 0;
-					Uart.nOutOfCnt = 0;
-					Uart.dropPosition = 0;
-				}
-			}
-
-			/*if(error) {
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = error & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				return TRUE;
-			}*/
-		}
-
-	}
-	else {
-		bit = Uart.bitBuffer & 0xf0;
-		bit >>= 4;
-		bit ^= 0x0F; // drops become 1s ;-)
-		if(bit) {
-			// should have been high or at least (4 * 128) / fc
-			// according to ISO this should be at least (9 * 128 + 20) / fc
-			if(Uart.highCnt == 8) {
-				// we went low, so this could be start of communication
-				// it turns out to be safer to choose a less significant
-				// syncbit... so we check whether the neighbour also represents the drop
-				Uart.posCnt = 1;   // apparently we are busy with our first half bit period
-				Uart.syncBit = bit & 8;
-				Uart.samples = 3;
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 4; Uart.samples = 2; }
-				else if(bit & 4)	{ Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 2; Uart.samples = 1; }
-				else if(bit & 2)	{ Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 1; Uart.samples = 0;
-					if(Uart.syncBit && (Uart.bitBuffer & 8)) {
-						Uart.syncBit = 8;
-
-						// the first half bit period is expected in next sample
-						Uart.posCnt = 0;
-						Uart.samples = 3;
-					}
-				}
-				else if(bit & 1)	{ Uart.syncBit = bit & 1; Uart.samples = 0; }
-
-				Uart.syncBit <<= 4;
-				Uart.state = STATE_START_OF_COMMUNICATION;
-				Uart.bitCnt = 0;
-				Uart.byteCnt = 0;
-				Uart.nOutOfCnt = 0;
-				Uart.OutOfCnt = 4; // Start at 1/4, could switch to 1/256
-				Uart.dropPosition = 0;
-				Uart.shiftReg = 0;
-				//error = 0;
-			}
-			else {
-				Uart.highCnt = 0;
-			}
-		}
-		else {
-			if(Uart.highCnt < 8) {
-				Uart.highCnt++;
-			}
-		}
-	}
+#define ICLASS_BUFFER_SIZE 34                // we expect max 34 bytes as tag answer (response to READ4)
 
-    return FALSE;
-}
 
 //=============================================================================
-// Manchester
-//=============================================================================
-
-static struct {
-    enum {
-        DEMOD_UNSYNCD,
-		DEMOD_START_OF_COMMUNICATION,
-		DEMOD_START_OF_COMMUNICATION2,
-		DEMOD_START_OF_COMMUNICATION3,
-		DEMOD_SOF_COMPLETE,
-		DEMOD_MANCHESTER_D,
-		DEMOD_MANCHESTER_E,
-		DEMOD_END_OF_COMMUNICATION,
-		DEMOD_END_OF_COMMUNICATION2,
-		DEMOD_MANCHESTER_F,
-        DEMOD_ERROR_WAIT
-    }       state;
-    int     bitCount;
-    int     posCount;
-	int     syncBit;
-    uint16_t    shiftReg;
-	int     buffer;
-	int     buffer2;
-	int	buffer3;
-	int     buff;
-	int     samples;
-    int     len;
-	enum {
-		SUB_NONE,
-		SUB_FIRST_HALF,
-		SUB_SECOND_HALF,
-		SUB_BOTH
-	}		sub;
-    uint8_t *output;
-} Demod;
-
-static RAMFUNC int ManchesterDecoding(int v)
-{
-	int bit;
-	int modulation;
-	int error = 0;
-
-	bit = Demod.buffer;
-	Demod.buffer = Demod.buffer2;
-	Demod.buffer2 = Demod.buffer3;
-	Demod.buffer3 = v;
-
-	if(Demod.buff < 3) {
-		Demod.buff++;
-		return FALSE;
-	}
-
-	if(Demod.state==DEMOD_UNSYNCD) {
-		Demod.output[Demod.len] = 0xfa;
-		Demod.syncBit = 0;
-		//Demod.samples = 0;
-		Demod.posCount = 1;		// This is the first half bit period, so after syncing handle the second part
-
-		if(bit & 0x08) {
-			Demod.syncBit = 0x08;
-		}
-
-		if(bit & 0x04) {
-			if(Demod.syncBit) {
-				bit <<= 4;
-			}
-			Demod.syncBit = 0x04;
-		}
-
-		if(bit & 0x02) {
-			if(Demod.syncBit) {
-				bit <<= 2;
-			}
-			Demod.syncBit = 0x02;
-		}
-
-		if(bit & 0x01 && Demod.syncBit) {
-			Demod.syncBit = 0x01;
-		}
-		
-		if(Demod.syncBit) {
-			Demod.len = 0;
-			Demod.state = DEMOD_START_OF_COMMUNICATION;
-			Demod.sub = SUB_FIRST_HALF;
-			Demod.bitCount = 0;
-			Demod.shiftReg = 0;
-			Demod.samples = 0;
-			if(Demod.posCount) {
-				//if(trigger) LED_A_OFF();  // Not useful in this case...
-				switch(Demod.syncBit) {
-					case 0x08: Demod.samples = 3; break;
-					case 0x04: Demod.samples = 2; break;
-					case 0x02: Demod.samples = 1; break;
-					case 0x01: Demod.samples = 0; break;
-				}
-				// SOF must be long burst... otherwise stay unsynced!!!
-				if(!(Demod.buffer & Demod.syncBit) || !(Demod.buffer2 & Demod.syncBit)) {
-					Demod.state = DEMOD_UNSYNCD;
-				}
-			}
-			else {
-				// SOF must be long burst... otherwise stay unsynced!!!
-				if(!(Demod.buffer2 & Demod.syncBit) || !(Demod.buffer3 & Demod.syncBit)) {
-					Demod.state = DEMOD_UNSYNCD;
-					error = 0x88;
-				}
-
-			}
-			error = 0;
-
-		}
-	}
-	else {
-		modulation = bit & Demod.syncBit;
-		modulation |= ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
-
-		Demod.samples += 4;
-
-		if(Demod.posCount==0) {
-			Demod.posCount = 1;
-			if(modulation) {
-				Demod.sub = SUB_FIRST_HALF;
-			}
-			else {
-				Demod.sub = SUB_NONE;
-			}
-		}
-		else {
-			Demod.posCount = 0;
-			/*(modulation && (Demod.sub == SUB_FIRST_HALF)) {
-				if(Demod.state!=DEMOD_ERROR_WAIT) {
-					Demod.state = DEMOD_ERROR_WAIT;
-					Demod.output[Demod.len] = 0xaa;
-					error = 0x01;
-				}
-			}*/
-			//else if(modulation) {
-			if(modulation) {
-				if(Demod.sub == SUB_FIRST_HALF) {
-					Demod.sub = SUB_BOTH;
-				}
-				else {
-					Demod.sub = SUB_SECOND_HALF;
-				}
-			}
-			else if(Demod.sub == SUB_NONE) {
-				if(Demod.state == DEMOD_SOF_COMPLETE) {
-					Demod.output[Demod.len] = 0x0f;
-					Demod.len++;
-					Demod.state = DEMOD_UNSYNCD;
-//					error = 0x0f;
-					return TRUE;
-				}
-				else {
-					Demod.state = DEMOD_ERROR_WAIT;
-					error = 0x33;
-				}
-				/*if(Demod.state!=DEMOD_ERROR_WAIT) {
-					Demod.state = DEMOD_ERROR_WAIT;
-					Demod.output[Demod.len] = 0xaa;
-					error = 0x01;
-				}*/
-			}
-
-			switch(Demod.state) {
-				case DEMOD_START_OF_COMMUNICATION:
-					if(Demod.sub == SUB_BOTH) {
-						//Demod.state = DEMOD_MANCHESTER_D;
-						Demod.state = DEMOD_START_OF_COMMUNICATION2;
-						Demod.posCount = 1;
-						Demod.sub = SUB_NONE;
-					}
-					else {
-						Demod.output[Demod.len] = 0xab;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0xd2;
-					}
-					break;
-				case DEMOD_START_OF_COMMUNICATION2:
-					if(Demod.sub == SUB_SECOND_HALF) {
-						Demod.state = DEMOD_START_OF_COMMUNICATION3;
-					}
-					else {
-						Demod.output[Demod.len] = 0xab;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0xd3;
-					}
-					break;
-				case DEMOD_START_OF_COMMUNICATION3:
-					if(Demod.sub == SUB_SECOND_HALF) {
-//						Demod.state = DEMOD_MANCHESTER_D;
-						Demod.state = DEMOD_SOF_COMPLETE;
-						//Demod.output[Demod.len] = Demod.syncBit & 0xFF;
-						//Demod.len++;
-					}
-					else {
-						Demod.output[Demod.len] = 0xab;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0xd4;
-					}
-					break;
-				case DEMOD_SOF_COMPLETE:
-				case DEMOD_MANCHESTER_D:
-				case DEMOD_MANCHESTER_E:
-					// OPPOSITE FROM ISO14443 - 11110000 = 0 (1 in 14443)
-					//                          00001111 = 1 (0 in 14443)
-					if(Demod.sub == SUB_SECOND_HALF) { // SUB_FIRST_HALF
-						Demod.bitCount++;
-						Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;
-						Demod.state = DEMOD_MANCHESTER_D;
-					}
-					else if(Demod.sub == SUB_FIRST_HALF) { // SUB_SECOND_HALF
-						Demod.bitCount++;
-						Demod.shiftReg >>= 1;
-						Demod.state = DEMOD_MANCHESTER_E;
-					}
-					else if(Demod.sub == SUB_BOTH) {
-						Demod.state = DEMOD_MANCHESTER_F;
-					}
-					else {
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0x55;
-					}
-					break;
-
-				case DEMOD_MANCHESTER_F:
-					// Tag response does not need to be a complete byte!
-					if(Demod.len > 0 || Demod.bitCount > 0) {
-						if(Demod.bitCount > 1) {  // was > 0, do not interpret last closing bit, is part of EOF
-							Demod.shiftReg >>= (9 - Demod.bitCount);	// right align data
-							Demod.output[Demod.len] = Demod.shiftReg & 0xff;
-							Demod.len++;
-						}
-
-						Demod.state = DEMOD_UNSYNCD;
-						return TRUE;
-					}
-					else {
-						Demod.output[Demod.len] = 0xad;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0x03;
-					}
-					break;
-
-				case DEMOD_ERROR_WAIT:
-					Demod.state = DEMOD_UNSYNCD;
-					break;
-
-				default:
-					Demod.output[Demod.len] = 0xdd;
-					Demod.state = DEMOD_UNSYNCD;
-					break;
-			}
-
-			/*if(Demod.bitCount>=9) {
-				Demod.output[Demod.len] = Demod.shiftReg & 0xff;
-				Demod.len++;
-
-				Demod.parityBits <<= 1;
-				Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);
-
-				Demod.bitCount = 0;
-				Demod.shiftReg = 0;
-			}*/
-			if(Demod.bitCount>=8) {
-				Demod.shiftReg >>= 1;
-				Demod.output[Demod.len] = (Demod.shiftReg & 0xff);
-				Demod.len++;
-				Demod.bitCount = 0;
-				Demod.shiftReg = 0;
-			}
-
-			if(error) {
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				Demod.output[Demod.len] = error & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				Demod.output[Demod.len] = bit & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = Demod.buffer & 0xFF;
-				Demod.len++;
-				// Look harder ;-)
-				Demod.output[Demod.len] = Demod.buffer2 & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = Demod.syncBit & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				return TRUE;
-			}
-
-		}
-
-	} // end (state != UNSYNCED)
-
-    return FALSE;
-}
-
-//=============================================================================
-// Finally, a `sniffer' for iClass communication
+// A `sniffer' for iClass communication
 // Both sides of communication!
 //=============================================================================
-
-//-----------------------------------------------------------------------------
-// Record the sequence of commands sent by the reader to the tag, with
-// triggering so that we start recording at the point that the tag is moved
-// near the reader.
-//-----------------------------------------------------------------------------
-void RAMFUNC SnoopIClass(void)
-{
-
-
-    // We won't start recording the frames that we acquire until we trigger;
-    // a good trigger condition to get started is probably when we see a
-    // response from the tag.
-    //int triggered = FALSE; // FALSE to wait first for card
-
-    // The command (reader -> tag) that we're receiving.
-	// The length of a received command will in most cases be no more than 18 bytes.
-	// So 32 should be enough!
-	#define ICLASS_BUFFER_SIZE 32
-	uint8_t readerToTagCmd[ICLASS_BUFFER_SIZE];
-    // The response (tag -> reader) that we're receiving.
-	uint8_t tagToReaderResponse[ICLASS_BUFFER_SIZE];
-	
-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- 
- 	// free all BigBuf memory
-	BigBuf_free();
-    // The DMA buffer, used to stream samples from the FPGA
-    uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
- 
-	set_tracing(TRUE);
-	clear_trace();
-    iso14a_set_trigger(FALSE);
-
-	int lastRxCounter;
-    uint8_t *upTo;
-    int smpl;
-    int maxBehindBy = 0;
-
-    // Count of samples received so far, so that we can include timing
-    // information in the trace buffer.
-    int samples = 0;
-    rsamples = 0;
-
-    // Set up the demodulator for tag -> reader responses.
-	Demod.output = tagToReaderResponse;
-    Demod.len = 0;
-    Demod.state = DEMOD_UNSYNCD;
-
-    // Setup for the DMA.
-    FpgaSetupSsc();
-    upTo = dmaBuf;
-    lastRxCounter = DMA_BUFFER_SIZE;
-    FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
-
-    // And the reader -> tag commands
-    memset(&Uart, 0, sizeof(Uart));
-	Uart.output = readerToTagCmd;
-    Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
-    Uart.state = STATE_UNSYNCD;
-
-    // And put the FPGA in the appropriate mode
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-
-	uint32_t time_0 = GetCountSspClk();
-	uint32_t time_start = 0;
-	uint32_t time_stop  = 0;
-
-    int div = 0;
-    //int div2 = 0;
-    int decbyte = 0;
-    int decbyter = 0;
-
-    // And now we loop, receiving samples.
-    for(;;) {
-        LED_A_ON();
-        WDT_HIT();
-        int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
-                                (DMA_BUFFER_SIZE-1);
-        if(behindBy > maxBehindBy) {
-            maxBehindBy = behindBy;
-            if(behindBy > (9 * DMA_BUFFER_SIZE / 10)) {
-                Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
-                goto done;
-            }
-        }
-        if(behindBy < 1) continue;
-
-	LED_A_OFF();
-        smpl = upTo[0];
-        upTo++;
-        lastRxCounter -= 1;
-        if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
-            upTo -= DMA_BUFFER_SIZE;
-            lastRxCounter += DMA_BUFFER_SIZE;
-            AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
-            AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
-        }
-
-        //samples += 4;
-	samples += 1;
-
-	if(smpl & 0xF) {
-		decbyte ^= (1 << (3 - div));
-	}
-	
-	// FOR READER SIDE COMMUMICATION...
-
-	decbyter <<= 2;
-	decbyter ^= (smpl & 0x30);
-
-	div++;
-	
-	if((div + 1) % 2 == 0) {
-		smpl = decbyter;	
-		if(OutOfNDecoding((smpl & 0xF0) >> 4)) {
-		    rsamples = samples - Uart.samples;
-			time_stop = (GetCountSspClk()-time_0) << 4;
-		    LED_C_ON();
-
-			//if(!LogTrace(Uart.output,Uart.byteCnt, rsamples, Uart.parityBits,TRUE)) break;
-			//if(!LogTrace(NULL, 0, Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, 0, TRUE)) break;
-			if(tracing)	{
-				uint8_t parity[MAX_PARITY_SIZE];
-				GetParity(Uart.output, Uart.byteCnt, parity);
-				LogTrace(Uart.output,Uart.byteCnt, time_start, time_stop, parity, TRUE);
-			}
-
-
-			/* And ready to receive another command. */
-		    Uart.state = STATE_UNSYNCD;
-		    /* And also reset the demod code, which might have been */
-		    /* false-triggered by the commands from the reader. */
-		    Demod.state = DEMOD_UNSYNCD;
-		    LED_B_OFF();
-		    Uart.byteCnt = 0;
-		}else{
-			time_start = (GetCountSspClk()-time_0) << 4;
-		}
-		decbyter = 0;
-	}
-
-	if(div > 3) {
-		smpl = decbyte;
-		if(ManchesterDecoding(smpl & 0x0F)) {
-			time_stop = (GetCountSspClk()-time_0) << 4;
-
-			rsamples = samples - Demod.samples;
-		    LED_B_ON();
-
-			if(tracing)	{
-				uint8_t parity[MAX_PARITY_SIZE];
-				GetParity(Demod.output, Demod.len, parity);
-				LogTrace(Demod.output, Demod.len, time_start, time_stop, parity, FALSE);
-			}
-
-		    // And ready to receive another response.
-		    memset(&Demod, 0, sizeof(Demod));
-			Demod.output = tagToReaderResponse;
-		    Demod.state = DEMOD_UNSYNCD;
-		    LED_C_OFF();
-		}else{
-			time_start = (GetCountSspClk()-time_0) << 4;
-		}
-		
-		div = 0;
-		decbyte = 0x00;
-	}
-	//}
-
-        if(BUTTON_PRESS()) {
-            DbpString("cancelled_a");
-            goto done;
-        }
-    }
-
-    DbpString("COMMAND FINISHED");
-
-    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-	Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
-
-done:
-    AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
-    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-	Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
-    LED_A_OFF();
-    LED_B_OFF();
-    LED_C_OFF();
-    LED_D_OFF();
+void SnoopIClass(uint8_t jam_search_len, uint8_t *jam_search_string) {
+	SnoopIso15693(jam_search_len, jam_search_string);
 }
 
+
 void rotateCSN(uint8_t* originalCSN, uint8_t* rotatedCSN) {
-	int i; 
-	for(i = 0; i < 8; i++) {
+	int i;
+	for (i = 0; i < 8; i++) {
 		rotatedCSN[i] = (originalCSN[i] >> 3) | (originalCSN[(i+1)%8] << 5);
 	}
 }
 
-//-----------------------------------------------------------------------------
-// Wait for commands from reader
-// Stop when button is pressed
-// Or return TRUE when command is captured
-//-----------------------------------------------------------------------------
-static int GetIClassCommandFromReader(uint8_t *received, int *len, int maxLen)
-{
-    // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
-    // only, since we are receiving, not transmitting).
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
-    // Now run a `software UART' on the stream of incoming samples.
-    Uart.output = received;
-    Uart.byteCntMax = maxLen;
-    Uart.state = STATE_UNSYNCD;
-
-    for(;;) {
-        WDT_HIT();
-
-        if(BUTTON_PRESS()) return FALSE;
-
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = 0x00;
-        }
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-
-			if(OutOfNDecoding(b & 0x0f)) {
-				*len = Uart.byteCnt;
-				return TRUE;
-			}
-        }
-    }
-}
-
-static uint8_t encode4Bits(const uint8_t b)
-{
-	uint8_t c = b & 0xF;
-	// OTA, the least significant bits first
-	//         The columns are
-	//               1 - Bit value to send
-	//               2 - Reversed (big-endian)
-	//               3 - Encoded
-	//               4 - Hex values
-
-	switch(c){
-	//                          1       2         3         4
-	  case 15: return 0x55; // 1111 -> 1111 -> 01010101 -> 0x55
-	  case 14: return 0x95; // 1110 -> 0111 -> 10010101 -> 0x95
-	  case 13: return 0x65; // 1101 -> 1011 -> 01100101 -> 0x65
-	  case 12: return 0xa5; // 1100 -> 0011 -> 10100101 -> 0xa5
-	  case 11: return 0x59; // 1011 -> 1101 -> 01011001 -> 0x59
-	  case 10: return 0x99; // 1010 -> 0101 -> 10011001 -> 0x99
-	  case 9:  return 0x69; // 1001 -> 1001 -> 01101001 -> 0x69
-	  case 8:  return 0xa9; // 1000 -> 0001 -> 10101001 -> 0xa9
-	  case 7:  return 0x56; // 0111 -> 1110 -> 01010110 -> 0x56
-	  case 6:  return 0x96; // 0110 -> 0110 -> 10010110 -> 0x96
-	  case 5:  return 0x66; // 0101 -> 1010 -> 01100110 -> 0x66
-	  case 4:  return 0xa6; // 0100 -> 0010 -> 10100110 -> 0xa6
-	  case 3:  return 0x5a; // 0011 -> 1100 -> 01011010 -> 0x5a
-	  case 2:  return 0x9a; // 0010 -> 0100 -> 10011010 -> 0x9a
-	  case 1:  return 0x6a; // 0001 -> 1000 -> 01101010 -> 0x6a
-	  default: return 0xaa; // 0000 -> 0000 -> 10101010 -> 0xaa
-
-	}
-}
-
-//-----------------------------------------------------------------------------
-// Prepare tag messages
-//-----------------------------------------------------------------------------
-static void CodeIClassTagAnswer(const uint8_t *cmd, int len)
-{
-
-	/*
-	 * SOF comprises 3 parts;
-	 * * An unmodulated time of 56.64 us
-	 * * 24 pulses of 423.75 KHz (fc/32)
-	 * * A logic 1, which starts with an unmodulated time of 18.88us
-	 *   followed by 8 pulses of 423.75kHz (fc/32)
-	 *
-	 *
-	 * EOF comprises 3 parts:
-	 * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated
-	 *   time of 18.88us.
-	 * - 24 pulses of fc/32
-	 * - An unmodulated time of 56.64 us
-	 *
-	 *
-	 * A logic 0 starts with 8 pulses of fc/32
-	 * followed by an unmodulated time of 256/fc (~18,88us).
-	 *
-	 * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by
-	 * 8 pulses of fc/32 (also 18.88us)
-	 *
-	 * The mode FPGA_HF_SIMULATOR_MODULATE_424K_8BIT which we use to simulate tag,
-	 * works like this.
-	 * - A 1-bit input to the FPGA becomes 8 pulses on 423.5kHz (fc/32) (18.88us).
-	 * - A 0-bit inptu to the FPGA becomes an unmodulated time of 18.88us
-	 *
-	 * In this mode the SOF can be written as 00011101 = 0x1D
-	 * The EOF can be written as 10111000 = 0xb8
-	 * A logic 1 is 01
-	 * A logic 0 is 10
-	 *
-	 * */
-
-	int i;
 
+// Encode SOF only
+static void CodeIClassTagSOF() {
 	ToSendReset();
-
-	// Send SOF
 	ToSend[++ToSendMax] = 0x1D;
-
-	for(i = 0; i < len; i++) {
-		uint8_t b = cmd[i];
-		ToSend[++ToSendMax] = encode4Bits(b & 0xF); //Least significant half
-		ToSend[++ToSendMax] = encode4Bits((b >>4) & 0xF);//Most significant half
-	}
-
-	// Send EOF
-	ToSend[++ToSendMax] = 0xB8;
-	//lastProxToAirDuration  = 8*ToSendMax - 3*8 - 3*8;//Not counting zeroes in the beginning or end
-	// Convert from last byte pos to length
 	ToSendMax++;
 }
 
-// Only SOF 
-static void CodeIClassTagSOF()
-{
-	//So far a dummy implementation, not used
-	//int lastProxToAirDuration =0;
 
-	ToSendReset();
-	// Send SOF
-	ToSend[++ToSendMax] = 0x1D;
-//	lastProxToAirDuration  = 8*ToSendMax - 3*8;//Not counting zeroes in the beginning
-
-	// Convert from last byte pos to length
-	ToSendMax++;
+static void AppendCrc(uint8_t *data, int len) {
+	ComputeCrc14443(CRC_ICLASS, data, len, data+len, data+len+1);
 }
-#define MODE_SIM_CSN        0
-#define MODE_EXIT_AFTER_MAC 1
-#define MODE_FULLSIM        2
 
-int doIClassSimulation(int simulationMode, uint8_t *reader_mac_buf);
-/**
- * @brief SimulateIClass simulates an iClass card.
- * @param arg0 type of simulation
- *			- 0 uses the first 8 bytes in usb data as CSN
- *			- 2 "dismantling iclass"-attack. This mode iterates through all CSN's specified
- *			in the usb data. This mode collects MAC from the reader, in order to do an offline
- *			attack on the keys. For more info, see "dismantling iclass" and proxclone.com.
- *			- Other : Uses the default CSN (031fec8af7ff12e0)
- * @param arg1 - number of CSN's contained in datain (applicable for mode 2 only)
- * @param arg2
- * @param datain
- */
-void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain)
-{
-	uint32_t simType = arg0;
-	uint32_t numberOfCSNS = arg1;
-	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-
-	// Enable and clear the trace
-	set_tracing(TRUE);
-	clear_trace();
-	//Use the emulator memory for SIM
-	uint8_t *emulator = BigBuf_get_EM_addr();
-
-	if(simType == 0) {
-		// Use the CSN from commandline
-		memcpy(emulator, datain, 8);
-		doIClassSimulation(MODE_SIM_CSN,NULL);
-	}else if(simType == 1)
-	{
-		//Default CSN
-		uint8_t csn_crc[] = { 0x03, 0x1f, 0xec, 0x8a, 0xf7, 0xff, 0x12, 0xe0, 0x00, 0x00 };
-		// Use the CSN from commandline
-		memcpy(emulator, csn_crc, 8);
-		doIClassSimulation(MODE_SIM_CSN,NULL);
-	}
-	else if(simType == 2)
-	{
-
-		uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
-		Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
-		// In this mode, a number of csns are within datain. We'll simulate each one, one at a time
-		// in order to collect MAC's from the reader. This can later be used in an offlne-attack
-		// in order to obtain the keys, as in the "dismantling iclass"-paper.
-		int i = 0;
-		for( ; i < numberOfCSNS && i*8+8 < USB_CMD_DATA_SIZE; i++)
-		{
-			// The usb data is 512 bytes, fitting 65 8-byte CSNs in there.
-
-			memcpy(emulator, datain+(i*8), 8);
-			if(doIClassSimulation(MODE_EXIT_AFTER_MAC,mac_responses+i*8))
-			{
-				cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
-				return; // Button pressed
-			}
-		}
-		cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
-
-	}else if(simType == 3){
-		//This is 'full sim' mode, where we use the emulator storage for data.
-		doIClassSimulation(MODE_FULLSIM, NULL);
-	}
-	else{
-		// We may want a mode here where we hardcode the csns to use (from proxclone).
-		// That will speed things up a little, but not required just yet.
-		Dbprintf("The mode is not implemented, reserved for future use");
-	}
-	Dbprintf("Done...");
-
-}
 
 /**
  * @brief Does the actual simulation
- * @param csn - csn to use
- * @param breakAfterMacReceived if true, returns after reader MAC has been received.
  */
-int doIClassSimulation( int simulationMode, uint8_t *reader_mac_buf)
-{
+int doIClassSimulation(int simulationMode, uint8_t *reader_mac_buf) {
+
 	// free eventually allocated BigBuf memory
 	BigBuf_free_keep_EM();
 
-	uint8_t *csn = BigBuf_get_EM_addr();
-	uint8_t *emulator = csn;
-	uint8_t sof_data[] = { 0x0F} ;
+	uint16_t page_size = 32 * 8;
+	uint8_t current_page = 0;
+
+	// maintain cipher states for both credit and debit key for each page
+	State cipher_state_KC[8];
+	State cipher_state_KD[8];
+	State *cipher_state = &cipher_state_KD[0];
+
+	uint8_t *emulator = BigBuf_get_EM_addr();
+	uint8_t *csn = emulator;
+
 	// CSN followed by two CRC bytes
-	uint8_t anticoll_data[10] = { 0 };
-	uint8_t csn_data[10] = { 0 };
-	memcpy(csn_data,csn,sizeof(csn_data));
-	Dbprintf("Simulating CSN %02x%02x%02x%02x%02x%02x%02x%02x",csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
+	uint8_t anticoll_data[10];
+	uint8_t csn_data[10];
+	memcpy(csn_data, csn, sizeof(csn_data));
+	Dbprintf("Simulating CSN %02x%02x%02x%02x%02x%02x%02x%02x", csn[0], csn[1], csn[2], csn[3], csn[4], csn[5], csn[6], csn[7]);
 
 	// Construct anticollision-CSN
-	rotateCSN(csn_data,anticoll_data);
+	rotateCSN(csn_data, anticoll_data);
 
 	// Compute CRC on both CSNs
-	ComputeCrc14443(CRC_ICLASS, anticoll_data, 8, &anticoll_data[8], &anticoll_data[9]);
-	ComputeCrc14443(CRC_ICLASS, csn_data, 8, &csn_data[8], &csn_data[9]);
+	AppendCrc(anticoll_data, 8);
+	AppendCrc(csn_data, 8);
+
+	uint8_t diversified_key_d[8] = { 0x00 };
+	uint8_t diversified_key_c[8] = { 0x00 };
+	uint8_t *diversified_key = diversified_key_d;
+
+	// configuration block
+	uint8_t conf_block[10] = {0x12, 0xFF, 0xFF, 0xFF, 0x7F, 0x1F, 0xFF, 0x3C, 0x00, 0x00};
 
 	// e-Purse
-	uint8_t card_challenge_data[8] = { 0x00 };
-	if(simulationMode == MODE_FULLSIM)
-	{
-		//Card challenge, a.k.a e-purse is on block 2
-		memcpy(card_challenge_data,emulator + (8 * 2) , 8);
+	uint8_t card_challenge_data[8] = { 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+
+	if (simulationMode == ICLASS_SIM_MODE_FULL) {
+		// initialize from page 0
+		memcpy(conf_block, emulator + 8 * 1, 8);
+		memcpy(card_challenge_data, emulator + 8 * 2, 8); // e-purse
+		memcpy(diversified_key_d, emulator + 8 * 3, 8);   // Kd
+		memcpy(diversified_key_c, emulator + 8 * 4, 8);   // Kc
+	}
+
+	AppendCrc(conf_block, 8);
+
+	// save card challenge for sim2,4 attack
+	if (reader_mac_buf != NULL) {
+		memcpy(reader_mac_buf, card_challenge_data, 8);
+	}
+
+	if (conf_block[5] & 0x80) {
+		page_size = 256 * 8;
+	}
+
+	// From PicoPass DS:
+	// When the page is in personalization mode this bit is equal to 1.
+	// Once the application issuer has personalized and coded its dedicated areas, this bit must be set to 0:
+	// the page is then "in application mode".
+	bool personalization_mode = conf_block[7] & 0x80;
+
+	// chip memory may be divided in 8 pages
+	uint8_t max_page = conf_block[4] & 0x10 ? 0 : 7;
+
+	// Precalculate the cipher states, feeding it the CC
+	cipher_state_KD[0] = opt_doTagMAC_1(card_challenge_data, diversified_key_d);
+	cipher_state_KC[0] = opt_doTagMAC_1(card_challenge_data, diversified_key_c);
+	if (simulationMode == ICLASS_SIM_MODE_FULL) {
+		for (int i = 1; i < max_page; i++) {
+			uint8_t *epurse = emulator + i*page_size + 8*2;
+			uint8_t *Kd = emulator + i*page_size + 8*3;
+			uint8_t *Kc = emulator + i*page_size + 8*4;
+			cipher_state_KD[i] = opt_doTagMAC_1(epurse, Kd);
+			cipher_state_KC[i] = opt_doTagMAC_1(epurse, Kc);
+		}
 	}
 
 	int exitLoop = 0;
@@ -1086,886 +174,755 @@ int doIClassSimulation( int simulationMode, uint8_t *reader_mac_buf)
 
 	uint8_t *modulated_response;
 	int modulated_response_size = 0;
-	uint8_t* trace_data = NULL;
+	uint8_t *trace_data = NULL;
 	int trace_data_size = 0;
 
-
 	// Respond SOF -- takes 1 bytes
-	uint8_t *resp_sof = BigBuf_malloc(2);
+	uint8_t *resp_sof = BigBuf_malloc(1);
 	int resp_sof_Len;
 
 	// Anticollision CSN (rotated CSN)
 	// 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
-	uint8_t *resp_anticoll = BigBuf_malloc(28);
+	uint8_t *resp_anticoll = BigBuf_malloc(22);
 	int resp_anticoll_len;
 
-	// CSN
+	// CSN (block 0)
 	// 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
-	uint8_t *resp_csn = BigBuf_malloc(30);
+	uint8_t *resp_csn = BigBuf_malloc(22);
 	int resp_csn_len;
 
-	// e-Purse
+	// configuration (block 1) picopass 2ks
+	uint8_t *resp_conf = BigBuf_malloc(22);
+	int resp_conf_len;
+
+	// e-Purse (block 2)
 	// 18: Takes 2 bytes for SOF/EOF and 8 * 2 = 16 bytes (2 bytes/bit)
-	uint8_t *resp_cc = BigBuf_malloc(20);
+	uint8_t *resp_cc = BigBuf_malloc(18);
 	int resp_cc_len;
 
+	// Kd, Kc (blocks 3 and 4). Cannot be read. Always respond with 0xff bytes only
+	uint8_t *resp_ff = BigBuf_malloc(22);
+	int resp_ff_len;
+	uint8_t ff_data[10] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00};
+	AppendCrc(ff_data, 8);
+
+	// Application Issuer Area (block 5)
+	uint8_t *resp_aia = BigBuf_malloc(22);
+	int resp_aia_len;
+	uint8_t aia_data[10] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00};
+	AppendCrc(aia_data, 8);
+
 	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
-	memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
 	int len;
 
 	// Prepare card messages
-	ToSendMax = 0;
 
-	// First card answer: SOF
+	// First card answer: SOF only
 	CodeIClassTagSOF();
-	memcpy(resp_sof, ToSend, ToSendMax); resp_sof_Len = ToSendMax;
+	memcpy(resp_sof, ToSend, ToSendMax);
+	resp_sof_Len = ToSendMax;
 
 	// Anticollision CSN
-	CodeIClassTagAnswer(anticoll_data, sizeof(anticoll_data));
-	memcpy(resp_anticoll, ToSend, ToSendMax); resp_anticoll_len = ToSendMax;
+	CodeIso15693AsTag(anticoll_data, sizeof(anticoll_data));
+	memcpy(resp_anticoll, ToSend, ToSendMax);
+	resp_anticoll_len = ToSendMax;
+
+	// CSN (block 0)
+	CodeIso15693AsTag(csn_data, sizeof(csn_data));
+	memcpy(resp_csn, ToSend, ToSendMax);
+	resp_csn_len = ToSendMax;
+
+	// Configuration (block 1)
+	CodeIso15693AsTag(conf_block, sizeof(conf_block));
+	memcpy(resp_conf, ToSend, ToSendMax);
+	resp_conf_len = ToSendMax;
+
+	// e-Purse (block 2)
+	CodeIso15693AsTag(card_challenge_data, sizeof(card_challenge_data));
+	memcpy(resp_cc, ToSend, ToSendMax);
+	resp_cc_len = ToSendMax;
+
+	// Kd, Kc (blocks 3 and 4)
+	CodeIso15693AsTag(ff_data, sizeof(ff_data));
+	memcpy(resp_ff, ToSend, ToSendMax);
+	resp_ff_len = ToSendMax;
+
+	// Application Issuer Area (block 5)
+	CodeIso15693AsTag(aia_data, sizeof(aia_data));
+	memcpy(resp_aia, ToSend, ToSendMax);
+	resp_aia_len = ToSendMax;
 
-	// CSN
-	CodeIClassTagAnswer(csn_data, sizeof(csn_data));
-	memcpy(resp_csn, ToSend, ToSendMax); resp_csn_len = ToSendMax;
-
-	// e-Purse
-	CodeIClassTagAnswer(card_challenge_data, sizeof(card_challenge_data));
-	memcpy(resp_cc, ToSend, ToSendMax); resp_cc_len = ToSendMax;
-
-	//This is used for responding to READ-block commands or other data which is dynamically generated
-	uint8_t *data_response = BigBuf_malloc(8 * 2 + 2);
 	//This is used for responding to READ-block commands or other data which is dynamically generated
-	uint8_t *data_generic_trace = BigBuf_malloc(8 * 2 + 2);
-
-	// Start from off (no field generated)
-	//FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-	//SpinDelay(200);
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-	SpinDelay(100);
-	StartCountSspClk();
-	// We need to listen to the high-frequency, peak-detected path.
-	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-	FpgaSetupSsc();
-
-	// To control where we are in the protocol
-	int cmdsRecvd = 0;
-	uint32_t time_0 = GetCountSspClk();
-	uint32_t t2r_time =0;
-	uint32_t r2t_time =0;
+	uint8_t *data_generic_trace = BigBuf_malloc(32 + 2); // 32 bytes data + 2byte CRC is max tag answer
+	uint8_t *data_response = BigBuf_malloc( (32 + 2) * 2 + 2);
 
-	LED_A_ON();
 	bool buttonPressed = false;
+	enum { IDLE, ACTIVATED, SELECTED, HALTED } chip_state = IDLE;
 
-	while(!exitLoop) {
-
-		LED_B_OFF();
-		//Signal tracer
-		// Can be used to get a trigger for an oscilloscope..
-		LED_C_OFF();
+	while (!exitLoop) {
+		WDT_HIT();
 
-		if(!GetIClassCommandFromReader(receivedCmd, &len, 100)) {
+		uint32_t reader_eof_time = 0;
+		len = GetIso15693CommandFromReader(receivedCmd, MAX_FRAME_SIZE, &reader_eof_time);
+		if (len < 0) {
 			buttonPressed = true;
 			break;
 		}
-		r2t_time = GetCountSspClk();
-		//Signal tracer
-		LED_C_ON();
-
-		// Okay, look at the command now.
-		if(receivedCmd[0] == ICLASS_CMD_ACTALL ) {
-			// Reader in anticollission phase
-			modulated_response = resp_sof; modulated_response_size = resp_sof_Len; //order = 1;
-			trace_data = sof_data;
-			trace_data_size = sizeof(sof_data);
-		} else if(receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 1) {
-			// Reader asks for anticollission CSN
-			modulated_response = resp_anticoll; modulated_response_size = resp_anticoll_len; //order = 2;
-			trace_data = anticoll_data;
-			trace_data_size = sizeof(anticoll_data);
-			//DbpString("Reader requests anticollission CSN:");
-		} else if(receivedCmd[0] == ICLASS_CMD_SELECT) {
-			// Reader selects anticollission CSN.
+
+		// Now look at the reader command and provide appropriate responses
+		// default is no response:
+		modulated_response = NULL;
+		modulated_response_size = 0;
+		trace_data = NULL;
+		trace_data_size = 0;
+
+		if (receivedCmd[0] == ICLASS_CMD_ACTALL && len == 1) {
+			// Reader in anticollision phase
+			if (chip_state != HALTED) {
+				modulated_response = resp_sof;
+				modulated_response_size = resp_sof_Len;
+				chip_state = ACTIVATED;
+			}
+
+		} else if (receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 1) { // identify
+			// Reader asks for anticollision CSN
+			if (chip_state == SELECTED || chip_state == ACTIVATED) {
+				modulated_response = resp_anticoll;
+				modulated_response_size = resp_anticoll_len;
+				trace_data = anticoll_data;
+				trace_data_size = sizeof(anticoll_data);
+			}
+
+		} else if (receivedCmd[0] == ICLASS_CMD_SELECT && len == 9) {
+			// Reader selects anticollision CSN.
 			// Tag sends the corresponding real CSN
-			modulated_response = resp_csn; modulated_response_size = resp_csn_len; //order = 3;
-			trace_data = csn_data;
-			trace_data_size = sizeof(csn_data);
-			//DbpString("Reader selects anticollission CSN:");
-		} else if(receivedCmd[0] == ICLASS_CMD_READCHECK_KD) {
-			// Read e-purse (88 02)
-			modulated_response = resp_cc; modulated_response_size = resp_cc_len; //order = 4;
-			trace_data = card_challenge_data;
-			trace_data_size = sizeof(card_challenge_data);
-			LED_B_ON();
-		} else if(receivedCmd[0] == ICLASS_CMD_CHECK) {
+			if (chip_state == ACTIVATED || chip_state == SELECTED) {
+				if (!memcmp(receivedCmd+1, anticoll_data, 8)) {
+					modulated_response = resp_csn;
+					modulated_response_size = resp_csn_len;
+					trace_data = csn_data;
+					trace_data_size = sizeof(csn_data);
+					chip_state = SELECTED;
+				} else {
+					chip_state = IDLE;
+				}
+			} else if (chip_state == HALTED) {
+				// RESELECT with CSN
+				if (!memcmp(receivedCmd+1, csn_data, 8)) {
+					modulated_response = resp_csn;
+					modulated_response_size = resp_csn_len;
+					trace_data = csn_data;
+					trace_data_size = sizeof(csn_data);
+					chip_state = SELECTED;
+				}
+			}
+
+		} else if (receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 4) { // read block
+			uint16_t blockNo = receivedCmd[1];
+			if (chip_state == SELECTED) {
+				if (simulationMode == ICLASS_SIM_MODE_EXIT_AFTER_MAC) {
+					// provide defaults for blocks 0 ... 5
+					switch (blockNo) {
+						case 0: // csn (block 00)
+							modulated_response = resp_csn;
+							modulated_response_size = resp_csn_len;
+							trace_data = csn_data;
+							trace_data_size = sizeof(csn_data);
+							break;
+						case 1: // configuration (block 01)
+							modulated_response = resp_conf;
+							modulated_response_size = resp_conf_len;
+							trace_data = conf_block;
+							trace_data_size = sizeof(conf_block);
+							break;
+						case 2: // e-purse (block 02)
+							modulated_response = resp_cc;
+							modulated_response_size = resp_cc_len;
+							trace_data = card_challenge_data;
+							trace_data_size = sizeof(card_challenge_data);
+							// set epurse of sim2,4 attack
+							if (reader_mac_buf != NULL) {
+								memcpy(reader_mac_buf, card_challenge_data, 8);
+							}
+							break;
+						case 3:
+						case 4: // Kd, Kc, always respond with 0xff bytes
+							modulated_response = resp_ff;
+							modulated_response_size = resp_ff_len;
+							trace_data = ff_data;
+							trace_data_size = sizeof(ff_data);
+							break;
+						case 5: // Application Issuer Area (block 05)
+							modulated_response = resp_aia;
+							modulated_response_size = resp_aia_len;
+							trace_data = aia_data;
+							trace_data_size = sizeof(aia_data);
+							break;
+						// default: don't respond
+					}
+				} else if (simulationMode == ICLASS_SIM_MODE_FULL) {
+					if (blockNo == 3 || blockNo == 4) { // Kd, Kc, always respond with 0xff bytes
+						modulated_response = resp_ff;
+						modulated_response_size = resp_ff_len;
+						trace_data = ff_data;
+						trace_data_size = sizeof(ff_data);
+					} else { // use data from emulator memory
+						memcpy(data_generic_trace, emulator + current_page*page_size + 8*blockNo, 8);
+						AppendCrc(data_generic_trace, 8);
+						trace_data = data_generic_trace;
+						trace_data_size = 10;
+						CodeIso15693AsTag(trace_data, trace_data_size);
+						memcpy(data_response, ToSend, ToSendMax);
+						modulated_response = data_response;
+						modulated_response_size = ToSendMax;
+					}
+				}
+			}
+
+		} else if ((receivedCmd[0] == ICLASS_CMD_READCHECK_KD
+					|| receivedCmd[0] == ICLASS_CMD_READCHECK_KC) && receivedCmd[1] == 0x02 && len == 2) {
+			// Read e-purse (88 02 || 18 02)
+			if (chip_state == SELECTED) {
+				if(receivedCmd[0] == ICLASS_CMD_READCHECK_KD){
+					cipher_state = &cipher_state_KD[current_page];
+					diversified_key = diversified_key_d;
+				} else {
+					cipher_state = &cipher_state_KC[current_page];
+					diversified_key = diversified_key_c;
+				}
+				modulated_response = resp_cc;
+				modulated_response_size = resp_cc_len;
+				trace_data = card_challenge_data;
+				trace_data_size = sizeof(card_challenge_data);
+			}
+
+		} else if ((receivedCmd[0] == ICLASS_CMD_CHECK_KC
+					|| receivedCmd[0] == ICLASS_CMD_CHECK_KD) && len == 9) {
 			// Reader random and reader MAC!!!
-			if(simulationMode == MODE_FULLSIM)
-			{	//This is what we must do..
-				//Reader just sent us NR and MAC(k,cc * nr)
-				//The diversified key should be stored on block 3
-				//However, from a typical dump, the key will not be there
-				uint8_t diversified_key[8] = { 0 };
-
-				//Get the diversified key from emulator memory
-				memcpy(diversified_key, emulator+(8*3),8);
-				uint8_t ccnr[12] = { 0 };
-				//Put our cc there (block 2)
-				memcpy(ccnr, emulator + (8 * 2), 8);
-				//Put nr there
-				memcpy(ccnr+8, receivedCmd+1,4);
-				//Now, calc MAC
-				doMAC(ccnr,diversified_key, data_generic_trace);
+			if (chip_state == SELECTED) {
+				if (simulationMode == ICLASS_SIM_MODE_FULL) {
+					//NR, from reader, is in receivedCmd+1
+					opt_doTagMAC_2(*cipher_state, receivedCmd+1, data_generic_trace, diversified_key);
+					trace_data = data_generic_trace;
+					trace_data_size = 4;
+					CodeIso15693AsTag(trace_data, trace_data_size);
+					memcpy(data_response, ToSend, ToSendMax);
+					modulated_response = data_response;
+					modulated_response_size = ToSendMax;
+					//exitLoop = true;
+				} else { // Not fullsim, we don't respond
+					// We do not know what to answer, so lets keep quiet
+					if (simulationMode == ICLASS_SIM_MODE_EXIT_AFTER_MAC) {
+						if (reader_mac_buf != NULL) {
+							// save NR and MAC for sim 2,4
+							memcpy(reader_mac_buf + 8, receivedCmd + 1, 8);
+						}
+						exitLoop = true;
+					}
+				}
+			}
+
+		} else if (receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
+			if (chip_state == SELECTED) {
+				// Reader ends the session
+				modulated_response = resp_sof;
+				modulated_response_size = resp_sof_Len;
+				chip_state = HALTED;
+			}
+
+		} else if (simulationMode == ICLASS_SIM_MODE_FULL && receivedCmd[0] == ICLASS_CMD_READ4 && len == 4) {  // 0x06
+			//Read 4 blocks
+			if (chip_state == SELECTED) {
+				uint8_t blockNo = receivedCmd[1];
+				memcpy(data_generic_trace, emulator + current_page*page_size + blockNo*8, 8 * 4);
+				AppendCrc(data_generic_trace, 8 * 4);
 				trace_data = data_generic_trace;
-				trace_data_size = 4;
-				CodeIClassTagAnswer(trace_data , trace_data_size);
+				trace_data_size = 8 * 4 + 2;
+				CodeIso15693AsTag(trace_data, trace_data_size);
 				memcpy(data_response, ToSend, ToSendMax);
 				modulated_response = data_response;
 				modulated_response_size = ToSendMax;
-			}else
-			{	//Not fullsim, we don't respond
-				// We do not know what to answer, so lets keep quiet
-				modulated_response = resp_sof; modulated_response_size = 0;
-				trace_data = NULL;
-				trace_data_size = 0;
-				if (simulationMode == MODE_EXIT_AFTER_MAC){
-					// dbprintf:ing ...
-					Dbprintf("CSN: %02x %02x %02x %02x %02x %02x %02x %02x"
-							   ,csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
-					Dbprintf("RDR:  (len=%02d): %02x %02x %02x %02x %02x %02x %02x %02x %02x",len,
-							receivedCmd[0], receivedCmd[1], receivedCmd[2],
-							receivedCmd[3], receivedCmd[4], receivedCmd[5],
-							receivedCmd[6], receivedCmd[7], receivedCmd[8]);
-					if (reader_mac_buf != NULL)
-					{
-						memcpy(reader_mac_buf,receivedCmd+1,8);
+			}
+
+		} else if (receivedCmd[0] == ICLASS_CMD_UPDATE && (len == 12 || len == 14)) {
+			// We're expected to respond with the data+crc, exactly what's already in the receivedCmd
+			// receivedCmd is now UPDATE 1b | ADDRESS 1b | DATA 8b | Signature 4b or CRC 2b
+			if (chip_state == SELECTED) {
+				uint8_t blockNo = receivedCmd[1];
+				if (blockNo == 2) { // update e-purse
+					memcpy(card_challenge_data, receivedCmd+2, 8);
+					CodeIso15693AsTag(card_challenge_data, sizeof(card_challenge_data));
+					memcpy(resp_cc, ToSend, ToSendMax);
+					resp_cc_len = ToSendMax;
+					cipher_state_KD[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_d);
+					cipher_state_KC[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_c);
+					if (simulationMode == ICLASS_SIM_MODE_FULL) {
+						memcpy(emulator + current_page*page_size + 8*2, card_challenge_data, 8);
+					}
+				} else if (blockNo == 3) { // update Kd
+					for (int i = 0; i < 8; i++) {
+						if (personalization_mode) {
+							diversified_key_d[i] = receivedCmd[2 + i];
+						} else {
+							diversified_key_d[i] ^= receivedCmd[2 + i];
+						}
+					}
+					cipher_state_KD[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_d);
+					if (simulationMode == ICLASS_SIM_MODE_FULL) {
+						memcpy(emulator + current_page*page_size + 8*3, diversified_key_d, 8);
+					}
+				} else if (blockNo == 4) { // update Kc
+					for (int i = 0; i < 8; i++) {
+						if (personalization_mode) {
+							diversified_key_c[i] = receivedCmd[2 + i];
+						} else {
+							diversified_key_c[i] ^= receivedCmd[2 + i];
+						}
+					}
+					cipher_state_KC[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_c);
+					if (simulationMode == ICLASS_SIM_MODE_FULL) {
+						memcpy(emulator + current_page*page_size + 8*4, diversified_key_c, 8);
 					}
-					exitLoop = true;
+				} else if (simulationMode == ICLASS_SIM_MODE_FULL) { // update any other data block
+						memcpy(emulator + current_page*page_size + 8*blockNo, receivedCmd+2, 8);
 				}
+				memcpy(data_generic_trace, receivedCmd + 2, 8);
+				AppendCrc(data_generic_trace, 8);
+				trace_data = data_generic_trace;
+				trace_data_size = 10;
+				CodeIso15693AsTag(trace_data, trace_data_size);
+				memcpy(data_response, ToSend, ToSendMax);
+				modulated_response = data_response;
+				modulated_response_size = ToSendMax;
 			}
 
-		} else if(receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
-			// Reader ends the session
-			modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
-			trace_data = NULL;
-			trace_data_size = 0;
-		} else if(simulationMode == MODE_FULLSIM && receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 4){
-			//Read block
-			uint16_t blk = receivedCmd[1];
-			trace_data = emulator+(blk << 3);
-			trace_data_size = 8;
-			CodeIClassTagAnswer(trace_data , trace_data_size);
-			memcpy(data_response, ToSend, ToSendMax);
-			modulated_response = data_response;
-			modulated_response_size = ToSendMax;
-		}
-		else if(receivedCmd[0] == ICLASS_CMD_PAGESEL)
-		{//Pagesel
-			//Pagesel enables to select a page in the selected chip memory and return its configuration block
-			//Chips with a single page will not answer to this command
-			// It appears we're fine ignoring this.
-			//Otherwise, we should answer 8bytes (block) + 2bytes CRC
-		}
-		else {
-			//#db# Unknown command received from reader (len=5): 26 1 0 f6 a 44 44 44 44
-			// Never seen this command before
-			Dbprintf("Unknown command received from reader (len=%d): %x %x %x %x %x %x %x %x %x",
-			len,
-			receivedCmd[0], receivedCmd[1], receivedCmd[2],
-			receivedCmd[3], receivedCmd[4], receivedCmd[5],
-			receivedCmd[6], receivedCmd[7], receivedCmd[8]);
+		} else if (receivedCmd[0] == ICLASS_CMD_PAGESEL && len == 4) {
+			// Pagesel
+			// Chips with a single page will not answer to this command
+			// Otherwise, we should answer 8bytes (conf block 1) + 2bytes CRC
+			if (chip_state == SELECTED) {
+				if (simulationMode == ICLASS_SIM_MODE_FULL && max_page > 0) {
+					current_page = receivedCmd[1];
+					memcpy(data_generic_trace, emulator + current_page*page_size + 8*1, 8);
+					memcpy(diversified_key_d, emulator + current_page*page_size + 8*3, 8);
+					memcpy(diversified_key_c, emulator + current_page*page_size + 8*4, 8);
+					cipher_state = &cipher_state_KD[current_page];
+					personalization_mode = data_generic_trace[7] & 0x80;
+					AppendCrc(data_generic_trace, 8);
+					trace_data = data_generic_trace;
+					trace_data_size = 10;
+					CodeIso15693AsTag(trace_data, trace_data_size);
+					memcpy(data_response, ToSend, ToSendMax);
+					modulated_response = data_response;
+					modulated_response_size = ToSendMax;
+				}
+			}
+
+		} else if (receivedCmd[0] == 0x26 && len == 5) {
+			// standard ISO15693 INVENTORY command. Ignore.
+
+		} else {
+			// don't know how to handle this command
+			char debug_message[250]; // should be enough
+			sprintf(debug_message, "Unhandled command (len = %d) received from reader:", len);
+			for (int i = 0; i < len && strlen(debug_message) < sizeof(debug_message) - 3 - 1; i++) {
+				sprintf(debug_message + strlen(debug_message), " %02x", receivedCmd[i]);
+			}
+			Dbprintf("%s", debug_message);
 			// Do not respond
-			modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
-			trace_data = NULL;
-			trace_data_size = 0;
 		}
 
-		if(cmdsRecvd >  100) {
-			//DbpString("100 commands later...");
-			//break;
-		}
-		else {
-			cmdsRecvd++;
-		}
 		/**
-		A legit tag has about 380us delay between reader EOT and tag SOF.
+		A legit tag has about 273,4us delay between reader EOT and tag SOF.
 		**/
-		if(modulated_response_size > 0) {
-			SendIClassAnswer(modulated_response, modulated_response_size, 1);
-			t2r_time = GetCountSspClk();
+		if (modulated_response_size > 0) {
+			uint32_t response_time = reader_eof_time + DELAY_ICLASS_VCD_TO_VICC_SIM;
+			TransmitTo15693Reader(modulated_response, modulated_response_size, &response_time, 0, false);
+			LogTrace_ISO15693(trace_data, trace_data_size, response_time*32, response_time*32 + modulated_response_size*32*64, NULL, false);
 		}
 
-		if (tracing) {
-			uint8_t parity[MAX_PARITY_SIZE];
-			GetParity(receivedCmd, len, parity);
-			LogTrace(receivedCmd,len, (r2t_time-time_0)<< 4, (r2t_time-time_0) << 4, parity, TRUE);
-
-			if (trace_data != NULL) {
-				GetParity(trace_data, trace_data_size, parity);
-				LogTrace(trace_data, trace_data_size, (t2r_time-time_0) << 4, (t2r_time-time_0) << 4, parity, FALSE);
-			}
-			if(!tracing) {
-				DbpString("Trace full");
-				//break;
-			}
-
-		}
-		memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
 	}
 
-	//Dbprintf("%x", cmdsRecvd);
-	LED_A_OFF();
-	LED_B_OFF();
-	LED_C_OFF();
-
-	if(buttonPressed)
+	if (buttonPressed)
 	{
 		DbpString("Button pressed");
 	}
 	return buttonPressed;
 }
 
-static int SendIClassAnswer(uint8_t *resp, int respLen, int delay)
-{
-	int i = 0, d=0;//, u = 0, d = 0;
-	uint8_t b = 0;
+/**
+ * @brief SimulateIClass simulates an iClass card.
+ * @param arg0 type of simulation
+ *          - 0 uses the first 8 bytes in usb data as CSN
+ *          - 2 "dismantling iclass"-attack. This mode iterates through all CSN's specified
+ *          in the usb data. This mode collects MAC from the reader, in order to do an offline
+ *          attack on the keys. For more info, see "dismantling iclass" and proxclone.com.
+ *          - Other : Uses the default CSN (031fec8af7ff12e0)
+ * @param arg1 - number of CSN's contained in datain (applicable for mode 2 only)
+ * @param arg2
+ * @param datain
+ */
+void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain) {
 
-	//FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K);
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K_8BIT);
+	LED_A_ON();
 
-	AT91C_BASE_SSC->SSC_THR = 0x00;
-	FpgaSetupSsc();
-	while(!BUTTON_PRESS()) {
-		if((AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)){
-			b = AT91C_BASE_SSC->SSC_RHR; (void) b;
-		}
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)){
-			b = 0x00;
-			if(d < delay) {
-				d++;
-			}
-			else {
-				if( i < respLen){
-					b = resp[i];
-					//Hack
-					//b = 0xAC;
-				}
-				i++;
-			}
-			AT91C_BASE_SSC->SSC_THR = b;
-		}
+	Iso15693InitTag();
+	
+	uint32_t simType = arg0;
+	uint32_t numberOfCSNS = arg1;
 
-//		if (i > respLen +4) break;
-		if (i > respLen +1) break;
+	// Enable and clear the trace
+	set_tracing(true);
+	clear_trace();
+	//Use the emulator memory for SIM
+	uint8_t *emulator = BigBuf_get_EM_addr();
+
+	if (simType == ICLASS_SIM_MODE_CSN) {
+		// Use the CSN from commandline
+		memcpy(emulator, datain, 8);
+		doIClassSimulation(ICLASS_SIM_MODE_CSN, NULL);
+	} else if (simType == ICLASS_SIM_MODE_CSN_DEFAULT) {
+		//Default CSN
+		uint8_t csn[] = {0x03, 0x1f, 0xec, 0x8a, 0xf7, 0xff, 0x12, 0xe0};
+		memcpy(emulator, csn, 8);
+		doIClassSimulation(ICLASS_SIM_MODE_CSN, NULL);
+	} else if (simType == ICLASS_SIM_MODE_READER_ATTACK) {
+		uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
+		Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
+		// In this mode, a number of csns are within datain. We'll simulate each one, one at a time
+		// in order to collect MAC's from the reader. This can later be used in an offline-attack
+		// in order to obtain the keys, as in the "dismantling iclass"-paper.
+		int i;
+		for (i = 0; i < numberOfCSNS && i*16+16 <= USB_CMD_DATA_SIZE; i++) {
+			// The usb data is 512 bytes, fitting 32 responses (8 byte CC + 4 Byte NR + 4 Byte MAC = 16 Byte response).
+			memcpy(emulator, datain+(i*8), 8);
+			if (doIClassSimulation(ICLASS_SIM_MODE_EXIT_AFTER_MAC, mac_responses+i*16)) {
+				 // Button pressed
+				 break;
+			}
+			Dbprintf("CSN: %02x %02x %02x %02x %02x %02x %02x %02x",
+					datain[i*8+0], datain[i*8+1], datain[i*8+2], datain[i*8+3],
+					datain[i*8+4], datain[i*8+5], datain[i*8+6], datain[i*8+7]);
+			Dbprintf("NR,MAC: %02x %02x %02x %02x %02x %02x %02x %02x",
+					mac_responses[i*16+ 8], mac_responses[i*16+ 9], mac_responses[i*16+10], mac_responses[i*16+11],
+					mac_responses[i*16+12], mac_responses[i*16+13], mac_responses[i*16+14], mac_responses[i*16+15]);
+			SpinDelay(100); // give the reader some time to prepare for next CSN
+		}
+		cmd_send(CMD_ACK, CMD_SIMULATE_TAG_ICLASS, i, 0, mac_responses, i*16);
+	} else if (simType == ICLASS_SIM_MODE_FULL) {
+		//This is 'full sim' mode, where we use the emulator storage for data.
+		doIClassSimulation(ICLASS_SIM_MODE_FULL, NULL);
+	} else {
+		// We may want a mode here where we hardcode the csns to use (from proxclone).
+		// That will speed things up a little, but not required just yet.
+		Dbprintf("The mode is not implemented, reserved for future use");
 	}
 
-	return 0;
+	Dbprintf("Done...");
+
+	LED_A_OFF();
 }
 
+
 /// THE READER CODE
 
-//-----------------------------------------------------------------------------
-// Transmit the command (to the tag) that was placed in ToSend[].
-//-----------------------------------------------------------------------------
-static void TransmitIClassCommand(const uint8_t *cmd, int len, int *samples, int *wait)
-{
-  int c;
-  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-  AT91C_BASE_SSC->SSC_THR = 0x00;
-  FpgaSetupSsc();
-
-   if (wait)
-   {
-     if(*wait < 10) *wait = 10;
-     
-     for(c = 0; c < *wait;) {
-       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-         AT91C_BASE_SSC->SSC_THR = 0x00;		// For exact timing!
-         c++;
-       }
-       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-         volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-         (void)r;
-       }
-       WDT_HIT();
-     }
-
-   }
-
-
-  uint8_t sendbyte;
-  bool firstpart = TRUE;
-  c = 0;
-  for(;;) {
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-
-      // DOUBLE THE SAMPLES!
-      if(firstpart) {
-	sendbyte = (cmd[c] & 0xf0) | (cmd[c] >> 4); 
-      }
-      else {
-	sendbyte = (cmd[c] & 0x0f) | (cmd[c] << 4);
-        c++;
-      }
-      if(sendbyte == 0xff) {
-	sendbyte = 0xfe;
-      }
-      AT91C_BASE_SSC->SSC_THR = sendbyte;
-      firstpart = !firstpart;
-
-      if(c >= len) {
-        break;
-      }
-    }
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-      volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-      (void)r;
-    }
-    WDT_HIT();
-  }
-  if (samples) *samples = (c + *wait) << 3;
+static void ReaderTransmitIClass(uint8_t *frame, int len, uint32_t *start_time) {
+
+	CodeIso15693AsReader(frame, len);
+	TransmitTo15693Tag(ToSend, ToSendMax, start_time);
+	uint32_t end_time = *start_time + 32*(8*ToSendMax-4); // substract the 4 padding bits after EOF
+	LogTrace_ISO15693(frame, len, *start_time*4, end_time*4, NULL, true);
 }
 
 
-//-----------------------------------------------------------------------------
-// Prepare iClass reader command to send to FPGA
-//-----------------------------------------------------------------------------
-void CodeIClassCommand(const uint8_t * cmd, int len)
-{
-  int i, j, k;
-  uint8_t b;
-
-  ToSendReset();
-
-  // Start of Communication: 1 out of 4
-  ToSend[++ToSendMax] = 0xf0;
-  ToSend[++ToSendMax] = 0x00;
-  ToSend[++ToSendMax] = 0x0f;
-  ToSend[++ToSendMax] = 0x00;
-
-  // Modulate the bytes 
-  for (i = 0; i < len; i++) {
-    b = cmd[i];
-    for(j = 0; j < 4; j++) {
-      for(k = 0; k < 4; k++) {
-			if(k == (b & 3)) {
-				ToSend[++ToSendMax] = 0x0f;
-			}
-			else {
-				ToSend[++ToSendMax] = 0x00;
-			}
-      }
-      b >>= 2;
-    }
-  }
-
-  // End of Communication
-  ToSend[++ToSendMax] = 0x00;
-  ToSend[++ToSendMax] = 0x00;
-  ToSend[++ToSendMax] = 0xf0;
-  ToSend[++ToSendMax] = 0x00;
-
-  // Convert from last character reference to length
-  ToSendMax++;
+static bool sendCmdGetResponseWithRetries(uint8_t* command, size_t cmdsize, uint8_t* resp, size_t max_resp_size,
+										  uint8_t expected_size, uint8_t tries, uint32_t start_time, uint32_t timeout, uint32_t *eof_time) {
+	while (tries-- > 0) {
+		ReaderTransmitIClass(command, cmdsize, &start_time);
+		if (expected_size == GetIso15693AnswerFromTag(resp, max_resp_size, timeout, eof_time)) {
+			return true;
+		}
+	}
+	return false;//Error
 }
 
-void ReaderTransmitIClass(uint8_t* frame, int len)
-{
-	int wait = 0;
-	int samples = 0;
 
-	// This is tied to other size changes
-	CodeIClassCommand(frame,len);
+/**
+ * @brief Selects an iclass tag
+ * @param card_data where the CSN is stored for return
+ * @return false = fail
+ *         true = success
+ */
+static bool selectIclassTag(uint8_t *card_data, uint32_t *eof_time) {
+	uint8_t act_all[]      = { 0x0a };
+	uint8_t identify[]     = { 0x0c };
+	uint8_t select[]       = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
 
-	// Select the card
-	TransmitIClassCommand(ToSend, ToSendMax, &samples, &wait);
-	if(trigger)
-		LED_A_ON();
+	uint8_t resp[ICLASS_BUFFER_SIZE];
 
-	// Store reader command in buffer
-	if (tracing) {
-		uint8_t par[MAX_PARITY_SIZE];
-		GetParity(frame, len, par);
-		LogTrace(frame, len, rsamples, rsamples, par, TRUE);
-	}
-}
+	uint32_t start_time = GetCountSspClk();
 
-//-----------------------------------------------------------------------------
-// Wait a certain time for tag response
-//  If a response is captured return TRUE
-//  If it takes too long return FALSE
-//-----------------------------------------------------------------------------
-static int GetIClassAnswer(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
-{
-	// buffer needs to be 512 bytes
-	int c;
+	// Send act_all
+	ReaderTransmitIClass(act_all, 1, &start_time);
+	// Card present?
+	if (GetIso15693AnswerFromTag(resp, sizeof(resp), ICLASS_READER_TIMEOUT_ACTALL, eof_time) < 0) return false; //Fail
 
-	// Set FPGA mode to "reader listen mode", no modulation (listen
-	// only, since we are receiving, not transmitting).
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
+	//Send Identify
+	start_time = *eof_time + DELAY_ICLASS_VICC_TO_VCD_READER;
+	ReaderTransmitIClass(identify, 1, &start_time);
+	//We expect a 10-byte response here, 8 byte anticollision-CSN and 2 byte CRC
+	uint8_t len = GetIso15693AnswerFromTag(resp, sizeof(resp), ICLASS_READER_TIMEOUT_OTHERS, eof_time);
+	if (len != 10) return false; //Fail
 
-	// Now get the answer from the card
-	Demod.output = receivedResponse;
-	Demod.len = 0;
-	Demod.state = DEMOD_UNSYNCD;
+	//Copy the Anti-collision CSN to our select-packet
+	memcpy(&select[1], resp, 8);
+	//Select the card
+	start_time = *eof_time + DELAY_ICLASS_VICC_TO_VCD_READER;
+	ReaderTransmitIClass(select, sizeof(select), &start_time);
+	//We expect a 10-byte response here, 8 byte CSN and 2 byte CRC
+	len = GetIso15693AnswerFromTag(resp, sizeof(resp), ICLASS_READER_TIMEOUT_OTHERS, eof_time);
+	if (len != 10) return false; //Fail
 
-	uint8_t b;
-	if (elapsed) *elapsed = 0;
+	//Success - we got CSN
+	//Save CSN in response data
+	memcpy(card_data, resp, 8);
 
-	bool skip = FALSE;
+	return true;
+}
 
-	c = 0;
-	for(;;) {
-		WDT_HIT();
 
-	        if(BUTTON_PRESS()) return FALSE;
+// Select an iClass tag and read all blocks which are always readable without authentication
+void ReaderIClass(uint8_t flags) {
 
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-			AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!
-			if (elapsed) (*elapsed)++;
-		}
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			if(c < timeout) { c++; } else { return FALSE; }
-			b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-			skip = !skip;
-			if(skip) continue;
-		
-			if(ManchesterDecoding(b & 0x0f)) {
-				*samples = c << 3;
-				return  TRUE;
-			}
-		}
+	LED_A_ON();
+
+	uint8_t card_data[6 * 8] = {0};
+	memset(card_data, 0xFF, sizeof(card_data));
+	uint8_t resp[ICLASS_BUFFER_SIZE];
+	//Read conf block CRC(0x01) => 0xfa 0x22
+	uint8_t readConf[] = {ICLASS_CMD_READ_OR_IDENTIFY, 0x01, 0xfa, 0x22};
+	//Read e-purse block CRC(0x02) => 0x61 0x10
+	uint8_t readEpurse[] = {ICLASS_CMD_READ_OR_IDENTIFY, 0x02, 0x61, 0x10};
+	//Read App Issuer Area block CRC(0x05) => 0xde  0x64
+	uint8_t readAA[] = {ICLASS_CMD_READ_OR_IDENTIFY, 0x05, 0xde, 0x64};
+
+	uint8_t result_status = 0;
+
+	if (flags & FLAG_ICLASS_READER_INIT) {
+		Iso15693InitReader();
 	}
-}
 
-int ReaderReceiveIClass(uint8_t* receivedAnswer)
-{
-  int samples = 0;
-  if (!GetIClassAnswer(receivedAnswer,160,&samples,0)) return FALSE;
-  rsamples += samples;
-  if (tracing) {
-	uint8_t parity[MAX_PARITY_SIZE];
-	GetParity(receivedAnswer, Demod.len, parity);
-	LogTrace(receivedAnswer,Demod.len,rsamples,rsamples,parity,FALSE);
-  }
-  if(samples == 0) return FALSE;
-  return Demod.len;
-}
+	if (flags & FLAG_ICLASS_READER_CLEARTRACE) {
+		set_tracing(true);
+		clear_trace();
+		StartCountSspClk();
+	}
 
-void setupIclassReader()
-{
-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-    // Reset trace buffer
-	set_tracing(TRUE);
-	clear_trace();
+	uint32_t start_time = 0;
+	uint32_t eof_time = 0;
 
-    // Setup SSC
-    FpgaSetupSsc();
-    // Start from off (no field generated)
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-    SpinDelay(200);
+	if (selectIclassTag(resp, &eof_time)) {
+		result_status = FLAG_ICLASS_READER_CSN;
+		memcpy(card_data, resp, 8);
 
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+		start_time = eof_time + DELAY_ICLASS_VICC_TO_VCD_READER;
 
-    // Now give it time to spin up.
-    // Signal field is on with the appropriate LED
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-    SpinDelay(200);
-    LED_A_ON();
+		//Read block 1, config
+		if (flags & FLAG_ICLASS_READER_CONF) {
+			if (sendCmdGetResponseWithRetries(readConf, sizeof(readConf), resp, sizeof(resp), 10, 10, start_time, ICLASS_READER_TIMEOUT_OTHERS, &eof_time)) {
+				result_status |= FLAG_ICLASS_READER_CONF;
+				memcpy(card_data+8, resp, 8);
+			} else {
+				Dbprintf("Failed to read config block");
+			}
+			start_time = eof_time + DELAY_ICLASS_VICC_TO_VCD_READER;
+		}
 
-}
+		//Read block 2, e-purse
+		if (flags & FLAG_ICLASS_READER_CC) {
+			if (sendCmdGetResponseWithRetries(readEpurse, sizeof(readEpurse), resp, sizeof(resp), 10, 10, start_time, ICLASS_READER_TIMEOUT_OTHERS, &eof_time)) {
+				result_status |= FLAG_ICLASS_READER_CC;
+				memcpy(card_data + (8*2), resp, 8);
+			} else {
+				Dbprintf("Failed to read e-purse");
+			}
+			start_time = eof_time + DELAY_ICLASS_VICC_TO_VCD_READER;
+		}
 
-size_t sendCmdGetResponseWithRetries(uint8_t* command, size_t cmdsize, uint8_t* resp, uint8_t expected_size, uint8_t retries)
-{
-	while(retries-- > 0)
-	{
-		ReaderTransmitIClass(command, cmdsize);
-		if(expected_size == ReaderReceiveIClass(resp)){
-			return 0;
+		//Read block 5, AA
+		if (flags & FLAG_ICLASS_READER_AA) {
+			if (sendCmdGetResponseWithRetries(readAA, sizeof(readAA), resp, sizeof(resp), 10, 10, start_time, ICLASS_READER_TIMEOUT_OTHERS, &eof_time)) {
+				result_status |= FLAG_ICLASS_READER_AA;
+				memcpy(card_data + (8*5), resp, 8);
+			} else {
+				Dbprintf("Failed to read AA block");
+			}
 		}
 	}
-	return 1;//Error
+	
+	cmd_send(CMD_ACK, result_status, 0, 0, card_data, sizeof(card_data));
+
+	LED_A_OFF();
 }
 
-/**
- * @brief Talks to an iclass tag, sends the commands to get CSN and CC.
- * @param card_data where the CSN and CC are stored for return
- * @return 0 = fail
- *         1 = Got CSN
- *         2 = Got CSN and CC
- */
-uint8_t handshakeIclassTag(uint8_t *card_data)
-{
-	static uint8_t act_all[]     = { 0x0a };
-	static uint8_t identify[]    = { 0x0c };
-	static uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
-	static uint8_t readcheck_cc[]= { 0x88, 0x02 };
-	uint8_t resp[ICLASS_BUFFER_SIZE];
 
-	uint8_t read_status = 0;
+void iClass_Check(uint8_t *NRMAC) {
+	uint8_t check[9] = {ICLASS_CMD_CHECK_KD, 0x00};
+	uint8_t resp[4];
+	memcpy(check+1, NRMAC, 8);
+	uint32_t eof_time;
+	bool isOK = sendCmdGetResponseWithRetries(check, sizeof(check), resp, sizeof(resp), 4, 3, 0, ICLASS_READER_TIMEOUT_OTHERS, &eof_time);
+	cmd_send(CMD_ACK, isOK, 0, 0, resp, sizeof(resp));
+}
 
-	// Send act_all
-	ReaderTransmitIClass(act_all, 1);
-	// Card present?
-	if(!ReaderReceiveIClass(resp)) return read_status;//Fail
-	//Send Identify
-	ReaderTransmitIClass(identify, 1);
-	//We expect a 10-byte response here, 8 byte anticollision-CSN and 2 byte CRC
-	uint8_t len  = ReaderReceiveIClass(resp);
-	if(len != 10) return read_status;//Fail
 
-	//Copy the Anti-collision CSN to our select-packet
-	memcpy(&select[1],resp,8);
-	//Select the card
-	ReaderTransmitIClass(select, sizeof(select));
-	//We expect a 10-byte response here, 8 byte CSN and 2 byte CRC
-	len  = ReaderReceiveIClass(resp);
-	if(len != 10) return read_status;//Fail
-
-	//Success - level 1, we got CSN
-	//Save CSN in response data
-	memcpy(card_data,resp,8);
+void iClass_Readcheck(uint8_t block, bool use_credit_key) {
+	uint8_t readcheck[2] = {ICLASS_CMD_READCHECK_KD, block};
+	if (use_credit_key) {
+		readcheck[0] = ICLASS_CMD_READCHECK_KC;
+	}
+	uint8_t resp[8];
+	uint32_t eof_time;
+	bool isOK = sendCmdGetResponseWithRetries(readcheck, sizeof(readcheck), resp, sizeof(resp), 8, 3, 0, ICLASS_READER_TIMEOUT_OTHERS, &eof_time);
+	cmd_send(CMD_ACK, isOK, 0, 0, resp, sizeof(resp));
+}
 
-	//Flag that we got to at least stage 1, read CSN
-	read_status = 1;
 
-	// Card selected, now read e-purse (cc)
-	ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
-	if(ReaderReceiveIClass(resp) == 8) {
-		//Save CC (e-purse) in response data
-		memcpy(card_data+8,resp,8);
+static bool iClass_ReadBlock(uint8_t blockNo, uint8_t *readdata) {
+	uint8_t readcmd[] = {ICLASS_CMD_READ_OR_IDENTIFY, blockNo, 0x00, 0x00}; //0x88, 0x00 // can i use 0C?
+	uint8_t bl = blockNo;
+	uint16_t rdCrc = iclass_crc16(&bl, 1);
+	readcmd[2] = rdCrc >> 8;
+	readcmd[3] = rdCrc & 0xff;
+	uint8_t resp[10];
+	uint32_t eof_time;
 
-		//Got both
-		read_status = 2;
-	}
+	bool isOK = sendCmdGetResponseWithRetries(readcmd, sizeof(readcmd), resp, sizeof(resp), 10, 10, 0, ICLASS_READER_TIMEOUT_OTHERS, &eof_time);
+	memcpy(readdata, resp, sizeof(resp));
 
-	return read_status;
+	return isOK;
 }
 
-// Reader iClass Anticollission
-void ReaderIClass(uint8_t arg0) {
 
-    uint8_t card_data[24]={0};
-    uint8_t last_csn[8]={0};
-	
-    int read_status= 0;
-    bool abort_after_read = arg0 & FLAG_ICLASS_READER_ONLY_ONCE;
-	bool get_cc = arg0 & FLAG_ICLASS_READER_GET_CC;
-	set_tracing(TRUE);
-    setupIclassReader();
-
-    size_t datasize = 0;
-    while(!BUTTON_PRESS())
-    {
-
-		if(!tracing) {
-			DbpString("Trace full");
-			break;
-		}
-		WDT_HIT();
+void iClass_ReadBlk(uint8_t blockno) {
 
-		read_status = handshakeIclassTag(card_data);
-
-		if(read_status == 0) continue;
-		if(read_status == 1) datasize = 8;
-		if(read_status == 2) datasize = 16;
-
-		//Todo, read the public blocks 1,5 aswell:
-		//
-		// 0 : CSN (we already have)
-		// 1 : Configuration
-		// 2 : e-purse (we already have)
-		// (3,4 write-only)
-		// 5 Application issuer area
-		//
-		//Then we can 'ship' back the 8 * 5 bytes of data,
-		// with 0xFF:s in block 3 and 4.
-
-		LED_B_ON();
-		//Send back to client, but don't bother if we already sent this
-		if(memcmp(last_csn, card_data, 8) != 0)
-		{
-
-			if(!get_cc || (get_cc && read_status == 2))
-			{
-				cmd_send(CMD_ACK,read_status,0,0,card_data,datasize);
-				if(abort_after_read) {
-					LED_A_OFF();
-					return;
-				}
-				//Save that we already sent this....
-				memcpy(last_csn, card_data, 8);
-			}
-			//If 'get_cc' was specified and we didn't get a CC, we'll just keep trying...
-		}
-		LED_B_OFF();
-    }
-    cmd_send(CMD_ACK,0,0,0,card_data, 0);
-    LED_A_OFF();
+	LED_A_ON();
+
+	uint8_t readblockdata[10];
+	bool isOK = iClass_ReadBlock(blockno, readblockdata);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	LED_D_OFF();
+	cmd_send(CMD_ACK, isOK, 0, 0, readblockdata, 8);
+
+	LED_A_OFF();
 }
 
-void ReaderIClass_Replay(uint8_t arg0, uint8_t *MAC) {
 
-	uint8_t card_data[USB_CMD_DATA_SIZE]={0};
-	uint16_t block_crc_LUT[255] = {0};
+void iClass_Dump(uint8_t startblock, uint8_t numblks) {
 
-	{//Generate a lookup table for block crc
-		for(int block = 0; block < 255; block++){
-			char bl = block;
-			block_crc_LUT[block] = iclass_crc16(&bl ,1);
-		}
-	}
-	//Dbprintf("Lookup table: %02x %02x %02x" ,block_crc_LUT[0],block_crc_LUT[1],block_crc_LUT[2]);
+	LED_A_ON();
 
-	uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
-	uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
-	
-    uint16_t crc = 0;
-	uint8_t cardsize=0;
-	uint8_t mem=0;
-	
-	static struct memory_t{
-	  int k16;
-	  int book;
-	  int k2;
-	  int lockauth;
-	  int keyaccess;
-	} memory;
-	
-	uint8_t resp[ICLASS_BUFFER_SIZE];
-	
-    setupIclassReader();
-	set_tracing(TRUE);
+	uint8_t readblockdata[USB_CMD_DATA_SIZE+2] = {0};
+	bool isOK = false;
+	uint16_t blkCnt = 0;
 
-	while(!BUTTON_PRESS()) {
-	
-		WDT_HIT();
+	if (numblks > USB_CMD_DATA_SIZE / 8) {
+		numblks = USB_CMD_DATA_SIZE / 8;
+	}
 
-		if(!tracing) {
-			DbpString("Trace full");
+	for (blkCnt = 0; blkCnt < numblks; blkCnt++) {
+		isOK = iClass_ReadBlock(startblock+blkCnt, readblockdata+8*blkCnt);
+		if (!isOK) {
+			Dbprintf("Block %02X failed to read", startblock+blkCnt);
 			break;
 		}
-		
-		uint8_t read_status = handshakeIclassTag(card_data);
-		if(read_status < 2) continue;
+	}
 
-		//for now replay captured auth (as cc not updated)
-		memcpy(check+5,MAC,4);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	LED_D_OFF();
 
-		if(sendCmdGetResponseWithRetries(check, sizeof(check),resp, 4, 5))
-		{
-			Dbprintf("Error: Authentication Fail!");
-			continue;
-		}
+	cmd_send(CMD_ACK, isOK, blkCnt, 0, readblockdata, blkCnt*8);
 
-		//first get configuration block (block 1)
-		crc = block_crc_LUT[1];
-		read[1]=1;
-		read[2] = crc >> 8;
-		read[3] = crc & 0xff;
+	LED_A_OFF();
+}
 
-		if(sendCmdGetResponseWithRetries(read, sizeof(read),resp, 10, 10))
-		{
-			Dbprintf("Dump config (block 1) failed");
-			continue;
-		}
 
-		mem=resp[5];
-		memory.k16= (mem & 0x80);
-		memory.book= (mem & 0x20);
-		memory.k2= (mem & 0x8);
-		memory.lockauth= (mem & 0x2);
-		memory.keyaccess= (mem & 0x1);
+static bool iClass_WriteBlock_ext(uint8_t blockNo, uint8_t *data) {
 
-		cardsize = memory.k16 ? 255 : 32;
-		WDT_HIT();
-		//Set card_data to all zeroes, we'll fill it with data
-		memset(card_data,0x0,USB_CMD_DATA_SIZE);
-		uint8_t failedRead =0;
-		uint32_t stored_data_length =0;
-		//then loop around remaining blocks
-		for(int block=0; block < cardsize; block++){
-
-			read[1]= block;
-			crc = block_crc_LUT[block];
-			read[2] = crc >> 8;
-			read[3] = crc & 0xff;
-
-			if(!sendCmdGetResponseWithRetries(read, sizeof(read), resp, 10, 10))
-			{
-				Dbprintf("     %02x: %02x %02x %02x %02x %02x %02x %02x %02x",
-						 block, resp[0], resp[1], resp[2],
-						resp[3], resp[4], resp[5],
-						resp[6], resp[7]);
-
-				//Fill up the buffer
-				memcpy(card_data+stored_data_length,resp,8);
-				stored_data_length += 8;
-				if(stored_data_length +8 > USB_CMD_DATA_SIZE)
-				{//Time to send this off and start afresh
-					cmd_send(CMD_ACK,
-							 stored_data_length,//data length
-							 failedRead,//Failed blocks?
-							 0,//Not used ATM
-							 card_data, stored_data_length);
-					//reset
-					stored_data_length = 0;
-					failedRead = 0;
-				}
+	uint8_t write[16] = {ICLASS_CMD_UPDATE, blockNo};
+	memcpy(write+2, data, 12); // data + mac
+	AppendCrc(write+1, 13);
+	uint8_t resp[10];
+	bool isOK = false;
+	uint32_t eof_time = 0;
 
-			}else{
-				failedRead = 1;
-				stored_data_length +=8;//Otherwise, data becomes misaligned
-				Dbprintf("Failed to dump block %d", block);
-			}
+	isOK = sendCmdGetResponseWithRetries(write, sizeof(write), resp, sizeof(resp), 10, 3, 0, ICLASS_READER_TIMEOUT_UPDATE, &eof_time);
+	if (!isOK) {
+		return false;
+	}
+	
+	uint8_t all_ff[8] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+	if (blockNo == 2) {
+		if (memcmp(data+4, resp, 4) || memcmp(data, resp+4, 4)) { // check response. e-purse update swaps first and second half
+			return false;
 		}
-
-		//Send off any remaining data
-		if(stored_data_length > 0)
-		{
-			cmd_send(CMD_ACK,
-					 stored_data_length,//data length
-					 failedRead,//Failed blocks?
-					 0,//Not used ATM
-					 card_data, stored_data_length);
+	} else if (blockNo == 3 || blockNo == 4) {
+		if (memcmp(all_ff, resp, 8)) { // check response. Key updates always return 0xffffffffffffffff
+			return false;
+		}
+	} else {
+		if (memcmp(data, resp, 8)) { // check response. All other updates return unchanged data
+			return false;
 		}
-		//If we got here, let's break
-		break;
 	}
-	//Signal end of transmission
-	cmd_send(CMD_ACK,
-			 0,//data length
-			 0,//Failed blocks?
-			 0,//Not used ATM
-			 card_data, 0);
 
-	LED_A_OFF();
+	return true;
 }
 
-//2. Create Read method (cut-down from above) based off responses from 1. 
-//   Since we have the MAC could continue to use replay function.
-//3. Create Write method
-/*
-void IClass_iso14443A_write(uint8_t arg0, uint8_t blockNo, uint8_t *data, uint8_t *MAC) {
-	uint8_t act_all[]     = { 0x0a };
-	uint8_t identify[]    = { 0x0c };
-	uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
-	uint8_t readcheck_cc[]= { 0x88, 0x02 };
-	uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
-	uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
-	uint8_t write[]       = { 0x87, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
-	
-    uint16_t crc = 0;
-	
-	uint8_t* resp = (((uint8_t *)BigBuf) + 3560);
 
-	// Reset trace buffer
-    memset(trace, 0x44, RECV_CMD_OFFSET);
-	traceLen = 0;
+void iClass_WriteBlock(uint8_t blockNo, uint8_t *data) {
 
-	// Setup SSC
-	FpgaSetupSsc();
-	// Start from off (no field generated)
-	// Signal field is off with the appropriate LED
-	LED_D_OFF();
+	LED_A_ON();
+
+	bool isOK = iClass_WriteBlock_ext(blockNo, data);
+	if (isOK) {
+		Dbprintf("Write block [%02x] successful", blockNo);
+	} else {
+		Dbprintf("Write block [%02x] failed", blockNo);
+	}
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-	SpinDelay(200);
+	LED_D_OFF();
 
-	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+	cmd_send(CMD_ACK, isOK, 0, 0, 0, 0);
+	LED_A_OFF();
+}
 
-	// Now give it time to spin up.
-	// Signal field is on with the appropriate LED
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-	SpinDelay(200);
+
+void iClass_Clone(uint8_t startblock, uint8_t endblock, uint8_t *data) {
 
 	LED_A_ON();
 
-	for(int i=0;i<1;i++) {
-	
-		if(traceLen > TRACE_SIZE) {
-			DbpString("Trace full");
-			break;
-		}
-		
-		if (BUTTON_PRESS()) break;
-
-		// Send act_all
-		ReaderTransmitIClass(act_all, 1);
-		// Card present?
-		if(ReaderReceiveIClass(resp)) {
-			ReaderTransmitIClass(identify, 1);
-			if(ReaderReceiveIClass(resp) == 10) {
-				// Select card          
-				memcpy(&select[1],resp,8);
-				ReaderTransmitIClass(select, sizeof(select));
-
-				if(ReaderReceiveIClass(resp) == 10) {
-					Dbprintf("     Selected CSN: %02x %02x %02x %02x %02x %02x %02x %02x",
-					resp[0], resp[1], resp[2],
-					resp[3], resp[4], resp[5],
-					resp[6], resp[7]);
-				}
-				// Card selected
-				Dbprintf("Readcheck on Sector 2");
-				ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
-				if(ReaderReceiveIClass(resp) == 8) {
-				   Dbprintf("     CC: %02x %02x %02x %02x %02x %02x %02x %02x",
-					resp[0], resp[1], resp[2],
-					resp[3], resp[4], resp[5],
-					resp[6], resp[7]);
-				}else return;
-				Dbprintf("Authenticate");
-				//for now replay captured auth (as cc not updated)
-				memcpy(check+5,MAC,4);
-				Dbprintf("     AA: %02x %02x %02x %02x",
-					check[5], check[6], check[7],check[8]);
-				ReaderTransmitIClass(check, sizeof(check));
-				if(ReaderReceiveIClass(resp) == 4) {
-				   Dbprintf("     AR: %02x %02x %02x %02x",
-					resp[0], resp[1], resp[2],resp[3]);
-				}else {
-				  Dbprintf("Error: Authentication Fail!");
-				  return;
-				}
-				Dbprintf("Write Block");
-				
-				//read configuration for max block number
-				read_success=false;
-				read[1]=1;
-				uint8_t *blockno=&read[1];
-				crc = iclass_crc16((char *)blockno,1);
-				read[2] = crc >> 8;
-				read[3] = crc & 0xff;
-				while(!read_success){
-				      ReaderTransmitIClass(read, sizeof(read));
-				      if(ReaderReceiveIClass(resp) == 10) {
-					 read_success=true;
-					 mem=resp[5];
-					 memory.k16= (mem & 0x80);
-					 memory.book= (mem & 0x20);
-					 memory.k2= (mem & 0x8);
-					 memory.lockauth= (mem & 0x2);
-					 memory.keyaccess= (mem & 0x1);
-
-				      }
-				}
-				if (memory.k16){
-				  cardsize=255;
-				}else cardsize=32;
-				//check card_size
-				
-				memcpy(write+1,blockNo,1);
-				memcpy(write+2,data,8);
-				memcpy(write+10,mac,4);
-				while(!send_success){
-				  ReaderTransmitIClass(write, sizeof(write));
-				  if(ReaderReceiveIClass(resp) == 10) {
-				    write_success=true;
-				}
-			}//
+	int written = 0;
+	int total_blocks = (endblock - startblock) + 1;
+
+	for (uint8_t block = startblock; block <= endblock; block++) {
+		// block number
+		if (iClass_WriteBlock_ext(block, data + (block-startblock)*12)) {
+			Dbprintf("Write block [%02x] successful", block);
+			written++;
+		} else {
+			Dbprintf("Write block [%02x] failed", block);
 		}
-		WDT_HIT();
 	}
-	
+
+	if (written == total_blocks)
+		Dbprintf("Clone complete");
+	else
+		Dbprintf("Clone incomplete");
+
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	LED_D_OFF();
+
+	cmd_send(CMD_ACK, 1, 0, 0, 0, 0);
 	LED_A_OFF();
-}*/
+}